Suspicions rise over the origin of antiforeigner hostility that provoked assaults on American women

The word-of-mouth allegations spread rapidly throughout Guatemala: gringos are snatching babies and ripping out their vital organs for sale abroad. Eight babies, the whispers assured, were found with their stomachs slashed open. One had a $100 bill stuck in its abdomen, plus a note that said in English, "Thanks for your cooperation."

There was no evidence that such gruesome trade exists. But an anti-foreigner paranoia took root swiftly and with savage results. Two American women wrongly suspected of kidnapping children suffered attacks that left one victim near death.

The reasons for the hysteria are uncertain. Diplomats and fearful foreign residents believe...